Cleaning tool



F. J. CANNON GLEANING TOOL Nov. 10, 1942.

Filed June 24, 1941 INVENTOR I [YJC'ann on ATTORNEY Patented Nov. 10, 1942 UNITED STATES PATENT OFFICE cmsnnvo 'roor.

Frank Jess Cannon, Millbrae, alif., alsignor to American Telephone and Telegraph Company, a corporation of New York Application June 24,1941, Serial No. 399,552

4 Claims. (01. 51-170) This invention relates to tools, and more particularly to a type of tool for use in abradlng the surfaces of electrical contacts or the like.

In telephone ofiices, particularly those of the panel dial type, there are a great many multiple brush contacts that become "snagged or otherwise deteriorated. This deterioration at the brush contacts reduces their eiilciency and at times interferes with telephone service. It has heretofore been the practice to replace such brush contacts after they have become suiliciently deterlorated.

In accordance with this invention a power driven tool has been devised for the abrasive cleaning of these brush contacts in telephone oflices. The tool consists of a small motor set into a pistol grip having a trigger control. A small pulley is mounted on the end of the motor shaft, and this pulley is connected to another pulley (or pulleys) by an endless belt coated with abrasive material, the latter pulley (or pulleys) being mounted on an auxiliary shaft (or shafts). The auxiliary pulleys are held against the belt under pressure, thereby maintaining the belt taut This invention will be better understood from the more detailed description hereinafter following when read in connection with the accompanying drawing in which Figure 1 represents a longitudinal sectional view of the tool of this invention; Fig. 2 is a side view of the tool of this invention inserted between switch contacts to be abraded; Fig. 3 shows a front view of the pulley and belt portions of the tool; Fig. 4 shows an enlarged view of the auxiliary pulleys in place between switch contacts; and Fig. 5 illustrates a view along the line I, I of Fig. 1. Throughout the drawing like reference characters will be employed to designate like parts.

Referring to the drawing, the reference character i3 designates the butt of the gun-shaped tool of this invention. The butt [0 has a barrelshaped portion ii in which may be inserted the end of a removable motor l2, the motor l2 being fastened to the butt at. i3 and to the barrel porscrew-threaded member to the armature shaft of the motor I2, and this coupling may be controlled by a nut 23. The end portion of the main drive shaft 23 is screw-threaded and supports a pulley 25 which is similarly screw-threaded, so that upon rotation of the drive shaft "the pulley 25 will be similarly rotated. The pulley 25 carries a collar 21 formed of rubber or other like material which acts to reduce slippage between the pulley 25 and a belt 23 during its travel. The collar 21 is crown-shaped in a well-known manner. The belt 23 is coated on its outer surface with any well-known abrasive material as, for example, carborundum, or any compound thereof.

The butt ill and collar ll of the gun-shaped tool are supplied with a support which is inserted in an opening as shown, support 30 being retained by a thumb screw member 3|. The support 34 carries a housing 32 for a compression spring 34, which is enclosed within the housing 32. The upper end of the spring 34 is immovable while its lower end, which is in contact with a slidable tension member 35, moves with and applies pressure to the tension member 35, as will be explained. Two shafts 38 and 31 are mounted in the tension member 35 and auxiliary pulleys 38 and 33, respectively, revolve about these shafts. The endless belt 28 passes over the pulleys 25 and 33 and at the same time engages the opposite rounded surfaces of the intermediate pulley 38.

The tension member 35 is slotted at 45, and within the slot there is positioned a pin which is permanently fastened to the spring housing 32. The spring 34 within the housing 32 applies continuous pressure against the tension member 35 tending to move the tension member in a. downward direction, that is, away from the upper pulley 25. The pin 48 limits the downward travel of the member 35. The upper end of member 35 is square-shaped so as to freely traverse the opening in the housing 32. At the same time the tension member 35 acts so as to continuously urge the pulley 33 against the belt 28, thereby maintaining the belt 28 under tension at all times tion at l4. A nut II is employed to hold the outduring its transmission. This tension member facilitates the use with the tool of commercial belts which vary in length without modifying the structure of the tool. The member 85 also prevents over-strain of the belt and facilitates the installation of the belt.

A flat-headed spacer 48 is held against the housing 32 and is fastened to support 30 by means of a screw member 50. The member 50 traverses an opening in housing 32 and engages a threaded opening in the end of support 58. The spacer 48 is preferably made of some good insulating material, as, for example, Bakelite or hard rubber. The flat-headed portion of spacer 48 is employed to act, not alone as a spacer but also as a rest when brought against a bank of terminals such as 52. The central portion of the spacer 48 is intermediate of the two sides of the belt 28, as will be more clearly seen in Figs. 2 and 3. The spring housing 82 is of square crosssection, while the support 30 may be of circular cross-section but square-ended to properly fit into the opening of the housing 32.

The auxiliary pulleys 38 and 38 are also crownshaped and of such small dimensions that they may be inserted within the very limited spaces provided.by the multiple brush contacts 55-56 shown in enlarged scale in Fig. 4. When brought into position the pulleys 38 and 39 will be in continuous contact with the belt member 28. After the trigger I8 is manipulated to operate the mechanism, the surface of any one of the contacts 55-56 will be abraded within buta few seconds, thereby eliminating the snagging surface of the contact.

By employing two pulleys such as 38 and 39 as shown, the lateral displacement of the belt 28 intermediate these pulleys will be reduced to a very small extent. In other words, the opposite sides of belt 28 will be maintained at a uniform spacing throughout the abrading operations.

While this invention has been shown and described in certain particular arangements merely for the purpose of illustration, it will be understood that the general principles of this invention will be applied to other and widely varied organizations without departing from the spirit of the invention and the scope of the appended claims.

What is claimed is:

1. A trigger-controlled power driven portable tool comprising a support, a motor carried by said support and having a main shaft, a pulley by said support, a pulley mechanically coupled to the armature of the motor, two auxiliary pulleys mounted on said support so that their shafts are in linear alinement with the pulley coupled to the motor, an endless belt having an outer abrasive surface which passes over all of said pulleys, and means for urging said two auxiliary pulleys against said belt, whereby the abrasive surface of the belt intermediate the auxiliary pulleys may be employed for abrading operations.

3. A hand-controlled gun-shaped power driven portable tool, comprising a support, a motor carried by said support, a first pulley coupled to the motor, a second pulley mounted on said support, an endless belt passing over both pulleys, the outer surface of said belt being formed of an abrasive material, means for longitudinally urging said second pulley against said belt, means including a device interposed intermediate of said first and second pulleys and in contact with both inner sides of said belt for preventing any substantial lateral displacement of said belt throughout its abrading operations, and a trigger mounted on said support for controlling the operation of said motor.

4. A hand-controlled gun-shaped power driven portable tool comprising a support, a motor mounted on said support, an endless abrasive belt, two devices for carrying the belt, one of said devices being coupled to the motor to rotate therewith and drive the belt, the other of said devices being mounted on said support, means carried by said support for continuously urging said devices againstsaid belt, means including a roller interposed intermediate of said devices and in contact with both inner sides of said belt for preventing any substantial lateral displacement of said belt throughout its abrading operations, and a trigger mounted on said support for controlling the operation of said motor.

FRANK JESS CANNON. 

